A wide range of lasers from the UV to the IR are selected based on their optical power and spectral characteristics to
match the particular absorption behavior for the material to be processed. Periodic microlens arrays are often used as
multi-aperture integrators to transform the Gaussian or non-uniform beam profile into a homogenized intensity profile
either in 1-D or 2-D distribution. Each microlens element samples the input inhomogeneous beam and spreads it over a
given angular distribution. Incoherent beams that are either temporally or spatially incoherent can produce very uniform
intensity profiles. However, coherent beams will experience interference effects in the recombination of the beams
generated by each individual microlens element. For many applications, for example pulsed laser sources, it is not
possible to use a rotating or moving element, such as a rotating diffuser, to circumvent the interferences resulting from
the beam coherence. Micro-optical elements comprised of a randomly varying component can be used to help smooth
out the interference effects within the far-field intensity profile.